£16,000 is the bottom of the market even for a C152 so the next annual inspection will almost certainly cost a few thousand
Believe me that is nowhere near the bottom end of the market. The cost of annuals is so enormous these days that there are numerous organisations/individuals around at the moment that aren't flying their aircraft enough to meet the fixed maintenance costs and will virtually give their aroplane away just to avoid the bills. You just have to do a bit of research. And I'm not talking about tatty aircraft.
NS